Calk for football shoes



June 24, 1930. A. STELZ ER 1,763,426

GALK FOR FOOTBALL SHOES Filed Dec. 20. 1928 my?! 9 I, 1

J B 7 r2- 4 Patented June 24, 1930 lJtSAZt rarest series ADOLF STELZEE, 0F ZURICH, SWITZERLAND CALK FOR FOOTBALL SHOES Application filed December 20, 1928, Serial No. 327,291, and. in Switzerland. December 21, 1927.

The commonly used calks for football shoes and the like consist as a rule of superposed leather elements fixed on the shoe by means of nails. When the calks wear, the 5 nail heads project and are liable to injure other players. When the ground is hard and the calks are partly worn, the nails in the shoe are often very disagreeable during the playing. To replace the worn calks by fresh ones, the nails have to be pulled out of the shoes so that the nail holes remain in the soles which thereby lose their waterproofness.

To avoid these inconveniences it has already been proposed, to use calks consisting of two elements screwed the one in theother so that these elements can be replaced as soon as they have worn. These calks have however not been generally adopted as they cannot withstand the stresses to which they .are submitted. The securing of the elements screwed together and the fixation on the shoe were unsatisfactory and the calks liable to break easily.

This invention has for its object to improve the calks, specially those designed for football shoes, so that the inconveniences of the hitherto used calks are avoided. With this object in view the calk is composed of two elements removably connected, one of the elements being constructed so that it can be first sunk in the sole, the other element submitted to wear being removably mounted in the first mentioned element. Means are further provided to lock together the two elements.

An embodiment of the invention is illustrated by way of example in the accompanying drawing in which:

it Fig. 1 shows in side elevation, partly in section, the calk fixed on the sole.

Fig. 2 shows in vertical section the calk head.

Fig. 3 is a top plan view of Fig. 2.

Fig. 4 shows in vertical section the upper element of the calk and Fig. 5 is a top plan view of Fig. 4. The calk is composed of the upper element 1 and of the head 2 screwed into the upper 9 element. The upper element 1 comprises a cylindrical holding body 3 with an internally threaded bore 4: and a conical'top plate 5. This conical top plate is inserted into an accordingly shaped hole 6 of the sole 7 The top plate 5 has nail holes 8 for nails 9 engaging with the upper layer 7 of the sole. The conicity of the plate5 ensures a secure seat in the sole 7.

Into the'threaded bore 4: an externally "threaded stud 10 of the calk head 2 is screwed. The calk head has in its upper surface an annular groove 11 so that a circular flange 12 is formed. The inner diameter of the annular groove 11 is slightly conical in order to ensure a resilient tighten-- ing and thereby a greater protection against automatic loosening. The end face of the cylindrical holding body 3 and the bottom of the annular groove 11 have flutes 13 engaging with one another to give further security against accidental loosening. For the flutes teeth might be substituted.

To facilitate screwing on and removing of the calk head it may have a transverse bore designed to receive a nail to facilitate rotation.

The calk, according to the invention is preferably made of fibre, hard rubber or similar material. The improved calk does not only increase the security of standing for the football player but it facilitates the maintenance of the shoe; the danger of injury is considerably reduced as on the calk head no sharp projections are formed by wear.

The calk, according to the invention may be used for other shoes and boots which have to be fitted with calks.

I claim 1- j 1. A calk for football boots, comprising in combination a circular top element fitted in the outer sole of the boot and bearing against th under sole of the boot and tapering towards the centre in downward direc tion, a tubular extension from the middle 5 of said top element projecting through the outer sole of the boot and having a screw threaded bore in the middle extending through the top element, a calk head having a cavity in is upper end, a screw threaded pin in the centre of said cavity adapted to engage in the screw thread of the bore in said top element, a fluted surface on the lower end of said tubular extension, and a fluted surface on the bottom of said cavity adapted to engage with the fluted surface of said tubular extension and to prevent the calk working loose.

2. A calk for football boots as specified in claim 1 in which the top element has holes through its tapered portion adapted to receive nails for fixing said top element to the inner sole of the boot, the outer rim of the cavity in the call: head engaging over said nails and preventing their falling out. In testimony whereof I affix my signature.

ADOLF STELZER. 

